Method of controlling battery usage

Abstract

There is provided a method of controlling battery usage of a first mobile device in a monitoring system for monitoring a plurality of mobile devices which are monitored at a server, the system comprising the server and the plurality of mobile devices monitored at the server, the plurality of mobile devices including the first mobile device, the first mobile device including a battery, the method comprising the steps of: (i) each mobile device acquiring location data; (ii) each mobile device sending the acquired location data to the server via a telecommunications network; (iii) the first mobile device receiving an instruction from the server to adjust how often the first mobile device reports location data to the server, so as to control a battery usage of the first mobile device.

1 . A method of controlling battery usage of a first mobile device in a monitoring system for monitoring a plurality of mobile devices which are monitored at a server, the system comprising the server and the plurality of mobile devices monitored at the server, the plurality of mobile devices including the first mobile device, the first mobile device including a battery, the method comprising the steps of:
 (i) each mobile device acquiring location data;   (ii) each mobile device sending the acquired location data to the server via a telecommunications network;   (iii) the first mobile device receiving an instruction from the server to adjust how often the first mobile device reports location data to the server, so as to control a battery usage of the first mobile device.   
     
     
         2 . Method of  claim 1 , including the step of: before step (iii), the first mobile device sending a report to the server of a battery level of the battery of the first mobile device. 
     
     
         3 . Method of any previous claim, including the step of: the server determining whether a position of the first mobile device has changed, and when a next position should be acquired by the first mobile device. 
     
     
         4 . Method of any previous claim, including the step of: the server performing a trade off calculation, in which the server adjusts the instructions sent to the first mobile device in response to a decreasing battery charge level of the first mobile device. 
     
     
         5 . Method of any previous claim, including the step of: calculating when to acquire the next position at the first mobile device in order to get enough information about the whereabouts of the first mobile device in order to ascertain the safety of the first mobile device. 
     
     
         6 . Method of any previous claim, including the step of: if the server determines the first mobile device is currently stationary, the server instructs the first mobile device to send the next position update to the server only when an application running on the first mobile device determines a significant location change of the first mobile device. 
     
     
         7 . Method of any previous claim, including the step of: if the server determines the first mobile device is currently travelling on a public transport journey, the server instructs the first mobile device to send the next position update to the server only when the public transport journey may next end (eg. at the next public transport station), as determined by the server. 
     
     
         8 . Method of any previous claim, including the step of: if the server determines the first mobile device is currently travelling on a public transport journey, the server instructs the first mobile device to send the next position update to the server only when the public transport journey is most likely to end, as determined by the server. 
     
     
         9 . Method of any previous claim, including the step of: the first mobile device monitoring its own position and if no position change is detected, position sending frequency is reduced by the first mobile device. 
     
     
         10 . Method of any previous claim, including the step of: the first mobile device monitoring its own position and if no position change is detected, position sending frequency is reduced to not sending position at all. 
     
     
         11 . Method of any previous claim, including the step of: the first mobile device monitoring its own position using its integral accelerometers. 
     
     
         12 . Method of any previous claim, including the step of: the first mobile device monitoring its own position and determining its position change to within an uncertainty level. 
     
     
         13 . Method of any previous claim, including the step of: the first mobile device monitoring its own position and position uncertainty using a GPS chip integral to the mobile device. 
     
     
         14 . Method of any previous claim, including the step of: the first mobile device monitoring its own position and position uncertainty using a GPS chip which returns a speed and a direction of movement. 
     
     
         15 . Method of any previous claim, including the step of: if a speed determined by the first mobile device is below a threshold level for longer than a threshold time period, the first mobile device concludes it is not moving. 
     
     
         16 . Method of any previous claim, including the step of: if the mobile device detects movement after an interval of being stationary, position sending is resumed by the first mobile device. 
     
     
         17 . Method of any previous claim, including the step of: the first mobile device investigating if it may be moving by checking if GSM cell IDs have changed since the previous time they were checked. 
     
     
         18 . Method of  claim 17 , including the step of: if it is determined that the first mobile device may be moving, the next step is for the first mobile device to obtain a GPS fix to see if indeed the first mobile device has moved since a previous GPS fix. 
     
     
         19 . Method of  claim 18 , including the step of: if the GPS fix indicates that there has not been a significant movement, the mobile device remains in a ‘rest mode’ to conserve battery power. 
     
     
         20 . Method of any previous claim, including the step of: the first mobile device functioning autonomously between communications with the server. 
     
     
         21 . Method of any previous claim, including the step of: when calculating a new position of the first mobile device, a GPS unit in the first mobile device remembers the last calculated position, almanac used, and UTC Time, but not which satellites were in view. 
     
     
         22 . Method of any previous claim, including the step of: the server instructing the first mobile device to calculate a GPS position with a lowest selectable accuracy level, so as to reduce battery power consumption. 
     
     
         23 . Method of any previous claim, including the step of: the server interrogating the first mobile device to determine a GPS chip being used by the first mobile device, and the server then selecting an accuracy level of the GPS position determination by the GPS chip, so as to achieve a required level of accuracy. 
     
     
         24 . Method of any previous claim, including the step of: a frequency of updates from the first mobile device following an SOS alert from the first mobile device being reduced by the server, in response to a low battery charge level of the first mobile device. 
     
     
         25 . Method of any previous claim, wherein the plurality of mobile devices are registered at the server. 
     
     
         26 . A monitoring system for monitoring a plurality of mobile devices at a server, the system comprising the server and the plurality of mobile devices, the plurality of mobile devices including a first mobile device, the first mobile device including a battery, the system configured such that:
 (i) each mobile device acquires location data;   (ii) each mobile device sends the acquired location data to the server via a telecommunications network;   (iii) the first mobile device is configured to receive an instruction from the server to adjust how often the first mobile device reports location data to the server, so as to control a battery usage of the first mobile device.   
     
     
         27 . The server of  claim 26 . 
     
     
         28 . The first mobile device of  claim 26 .